• Korean journal of applied entomology
• /
• v.43 no.3 s.136
• /
• pp.257-262
• /
• 2004

Toxicities of 51 pesticides (25 insecticides, 11, acaricides, 11 fungicides and 4 adjuvants) commonly used to control greenhouse insect, mite, and disease pests were evaluated to minute pirate bug, Orius strigicollis nymphs and adults at the recommended concentration. Among 25 insecticides tested, fipronil, lufenuron, acetamiprid+fipronil, $\alpha$-cypermethrin+flufenoxuron and buprofezin + amitraz showed low toxicity to O. strigicollis. Among acaricides, acequinocyl, bifenazate, chlorfenapyr, etoxazole, fenpyroximate, flufenoxuron, milbemectin, spirodiclofen and tebufenpyrad showed low toxicity to O. strigicollis. All fungicides and adjuvants tested were very low toxicity. It may be suggested from these results that five insecticides, nine acaricides, eleven fungicides and four adjuvants could be incorporated into the integrated thrips management system with O. strigicollis in greenhouses.

• The Journal of Bigdata
• /
• v.4 no.2
• /
• pp.207-220
• /
• 2019

Recent developments in information and communication technology has enabled the deployment of sensor based data to provide real-time services. In Korea, The Korea Transportation Safety Authority is collecting driving information of all commercial vehicles through a fitted digital tachograph (DTG). This information gathered using DTG can be utilized in various ways in the field of transportation. Notably in autonomous driving, the real-time analysis of this information can be used to prevent or respond to dangerous driving behavior. However, there is a limit to processing a large amount of data at a level suitable for real-time services using a traditional database system. In particular, due to a such technical problem, the processing of large quantity of traffic big data for real-time commercial vehicle operation information analysis has never been attempted in Korea. In order to solve this problem, this study optimized the new database server system and confirmed that a real-time service is possible. It is expected that the constructed database system will be used to secure base data needed to establish digital twin and autonomous driving environments.

• Advances in pediatric surgery
• /
• v.7 no.2
• /
• pp.112-117
• /
• 2001

With the advances in neonatal intensive care, pediatric surgeons experience very low birth weight infants, weighing <1,500 g, more frequently. We report our 14 cases of very low birth weight infants with intestinal perforations without congenital causes, at the Asan Medical Center during the 11-year period from 1989 to 2000. The average birth weight was 919 g(563-1,490), and average gestational age was 206 days(161-286). There were nine males and five females, Operation was performed at an average age of 14.0 days(3-38). Ten neonates with symptomatic PDA were given indomethacin in an attempt to close the ductus. Bowel perforation involved the jejunum in two and ileum in twelve. At laparotomy, there were seven focal intestinal perforations, five typical NEC, one intussusception, and an unknown cause, Four neonates underwent resection and anastomosis of the bowel, and nine underwent exteriorization. One underwent resection and anastomosis after peritoneal drainage. Four patients had postoperative complications; two leakage of anastomosis, one stoma necrosis, and one internal herniation. Seven of fourteen patients survived(50.0 %). Seven patients died of septic complication. There was a significant difference in the birth weight and gestational age in survivors compared with those who died(p<0.05). There was an increased risk of bowel perforation in indomethacin treatment for PDA. Careful clinical observation and keen judgment are essential for this particular group of infants.

• Advances in pediatric surgery
• /
• v.12 no.1
• /
• pp.1-10
• /
• 2006

Recent advances in neonatal management have resulted in a dramatic increase in survival of very low birth weight infants. These critically ill infants, however, continue to pose significant challenges in management and ethics. There is little information on the outcome of the micropremie (birth weight less than 800 g) that require surgery. The records of 171 micropremies treated over a 15 year period (beginning in 1989) at Asan Medical Center was reviewed retrospectively. Forty-one (24.0 %) infants required surgical interventions by pediatric surgeons. There were 90 boys and 81 girls. The smallest infant, weighed 396g at birth, had esophageal atresia and died before surgery. The smallest survivor, birth weight 645 g, received anenterostomy for necrotizing enterocolitis at the weight of 590 g. The gestational age of the group rangedfrom 21 to 36 weeks. The most common surgical problem was inguinal hernia. There were 20 inguinal hernias, and repairs were performed on17 infants. Excluding 2 cases, hernia repair was performed at the time of discharge. There was only one recurrence of adirect inguinal hernia. Necrotizing enterocolitis developed in 17 patients, 11 were operated upon, two had peritoneal drainages, and 9 had enterostomies. Five of 11 surgical infants died after operation and three of the nonsurgical infants died of various complications. Although micropremies have potentially high risks of serious complications and death, the outcome can improve with careful surgical observation and judgment.

• Composites Research
• /
• v.25 no.6
• /
• pp.211-216
• /
• 2012

FBG sensor peaks could be split due to polarization by shear strain, when the fiber optic sensors embedded or attached to the structure. For the fiber optic sensor packages, sensor grating has to be protected from shear strains. Also, pretension has to be applied to the sensor because compressive strain must be measured. Without pretension of sensor, the sensor does not show any change of signal until it is stretched. In order to mesure compressive and tensile strains, two fixing point and prestressed sensor need. In the fixing point, just holding the optical fiber cause slip between core and cladding in the fiber. A Fixation method of prestressed FBG sensors fixed with partially stripped fibers was developed. The sensor package has the prestress controllable fixtures at the fixing points. Prestress to the sensor imposed by controlling the two fixed points with bolts and nuts make it easy to measure compressive strain as well as tensile strain. The fiber optic sensor packages applied to the actual structure and the structural monitoring system using the package can be applied to safety through surveillance.

• The Journal of the Korea Contents Association
• /
• v.12 no.12
• /
• pp.126-134
• /
• 2012

The researchers of this study closely looked into the methods for cognitive-scientific approach to problems of marine design at a time when the overall values of marine cultures are acknowledged in full scale. To that end, the researchers analyzed the problems and problem-solving process for the initial approach to marine design. At the same time, the researchers made the matrix of the design-developmental directions by cognitive scientific approach. After selecting the subjects, the researchers collected verbal protocol and behavior protocol which were shown in the process of a designer's thinking. This was for the sake of protocol analysis which is the representative research technique of cognitive science. Based on the collected data, the researchers empirically analyzed the behavior patterns shown in the marine design process so as to develop the design behavior-graph pattern of designers in an objective and systematic way. The behavior graph was helpful for looking into the initial developmental directions of design and for predicting cognitive structure of designers. The researchers hope that this study will become a fundamental material for predicting cognitive directions of designer for planning and designing the marine design.

• Neonatal Medicine
• /
• v.15 no.2
• /
• pp.123-133
• /
• 2008

Purpose: The purpose of this study was to determine the outcomes of extremely low birth weight infants (ELBWI) who were born at the Asan Medical Center and evaluate the recent status of neonatal intensive care and associated problems. Methods:We retrospectively evaluated 120 inborn ELBWI who were admitted to the NICU of the Asan Medical Center between 2003 and 2006. The survival rate, neurodevelopmental outcomes, maternal and infant factors, and infant mordibities were evaluated and the relationships with survival and catch-up growth were investigated. Results:The survival rate of the ELBWI was 82% at a mean gestational age of 27+2 weeks, and with a mean birth weight of 801.3${\pm}$129.0 g. The duration of hospitalization was 85.7${\pm}$27.2 days, the duration of O2 use was 43.9${\pm}$35.4 days, and the duration of ventilatory support was 20.9${\pm}$20.9 days among the survivors. The incidence of respiratory distress syndrome, chronic lung disease, severe intraventricular hemorrhage, and periventricular leukomalacia were 41.8%, 61.2%, 3%, and 4%, respectively. The mean mental developmental index and psychomotor development index of Bailey Scales of Infant Development (II) at follow-up were 83.4${\pm}$18.2 and 83.3${\pm}$20.3, respectively. Among the infants who had >18 months of follow-up, 50.8% had catch-up growth at 12 months. Conclusion:The survival rate of ELBWI has improved; however, the morbidities remain high, thus indicating further efforts must be implemented to reduce morbidity and improve neurodevelopmental outcomes.

• Journal of the Korean Society for Nondestructive Testing
• /
• v.26 no.5
• /
• pp.315-320
• /
• 2006

This paper describes stress analysis and fatigue limit evaluation of plate with V-notch and hole-notch by lock-in infrared thermography. Temperature variation of a specimen under cyclic loading is negatively proportional to the sum of principle stress change and the surface temperature measured by infrared camera is calculated to the stress of notch specimens, based on thermoelastic equation. And also, fatigue limitation can be evaluated by the change of intrinsic energy dissipation. Fatigue limitation of two notch specimens is evaluated as 164 MPa and 185 MPa, respectively and the stress measured by Lock-in infrared Thermography show good agreement within 10% error.

• Journal of the Korean Society for Nondestructive Testing
• /
• v.26 no.5
• /
• pp.321-328
• /
• 2006

In this study, the deformation oi wall thinning elbow is measured and the position of the internal thinning defect is found out by shearography. Shearography is an optical method which has applied to nondestructive testing (NDT) and the strain/stress and deformation analysis. This technique has the merit of the directly measuring the first derivative of displacement with sensitivity which can be adjusted by handling the tilt mirror in the interferometer. In this paper, we tested carbon steel pipe locally wall thinned and loaded internal pressure and the shearography was applied to measure the out-of-plane deformation of wall thinning elbow and to investigate the internal thinning defect of it. From the results, it was confirmed that this technique is proper to the practical application on the pipe line system with internal defect.

• 한국해양학회지
• /
• v.28 no.4
• /
• pp.272-280
• /
• 1993

The seasonal variations of water salinity and the concentration of suspended particulate matter (SPM value) have been monitored in the Keum Estuary and its adjacent coastal area. the concentrations of suspended matters show great seasonal variations with low concentrations during summer season and high concentrations during winter season. During the flood season of summer, water salinities are less than 5% in the Keum estuary, and the brackish water (salinity<28%) prevails seaward covering the entire coastal area. The concentrations decreased abruptly to the seaward from higher than 100mg/l in the Keum estuary to less than 5 mg/l in the offshore. These phenomena probably results from the rapid e\deposition of riverine suspended matters within the Keum Estuary. The seasonal variations of suspended matter concentrations in the Keum Estuary and its adjacent coastal area are interpreted as the cyclic (seasonal) sedimentation processes in the west coast of Korea, that is, replenishment and deposition of fine sediments in summer, and resuspension and seaward transport in winter.